I don't think they count as undead but as manifestations of the virus dunno (like the hunters etc) dunno bout the zombie looking enemies though (yknow the people you just charge through for the lulz) depends on how it was interpreted
even if certian infected could be controlled with Foul's shenanigans (I don't think he could control the actual "threat" level infected like Hunters / Uber Hunters etc) but Alex could just "Omnom" of any that attack him and just heal up / get stronger.
<shrug>
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XBL GT: Demon Ninja X2
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